The enclosed application represents the development of a consortium of investigators who will carry out multicenter drug trials in Alzheimer's disease (AD). This consortium, containing 30 Alzheimer Disease Study Units (ADSUs), will critically examine existing instruments for the evaluation of AD patients participating in clinical drug trials. When appropriate, new instruments will be developed for use by this group. Specific drug trials proposed are a pilot study to examine the safety of nerve growth factor administered to a small number of AD patients. If safe, a multicenter double-blind, parallel, placebo-controlled trial examining both short- and long-term administration of nerve growth factor in 150 subjects is proposed. A second study examining the ability of deprenyl, a selective monoamine oxidase-B inhibitor, to slow the rate of decline in AD is also proposed. The second study will be a two-year, parallel, double-blind, placebo-controlled trial in 300 subjects. Additional drug trials are proposed for Years 4 and 5 of this grant. The specific drug trials included in this proposal are examples of trials that might be carried out by this consortium. Final decisions regarding which drugs are tested will be made in consultation with NIA and the NIA-appointed Oversight Committee.